1. Field of the Invention
The present invention is related to personal computers and more particularly to an apparatus that provides expansion card slots on a motherboard of a computer.
2. Background Art
A personal computer is a stand-alone desktop computer housed in a chassis which is a cover that protects the computer components from the environment and the environment from the computer, such as electromagnetic interference (EMI). Input/output (I/O) devices, such as a video monitor, mouse and printer are connected to a back panel of the chassis by means of cables that plug into connectors at a back panel of the chassis. Inside the chassis is a system board, called a motherboard, that holds the electronic components of the computer.
In past designs, up to eight receptacles (slots) are provided for adapter boards that allow compatible circuit boards (cards) to be added to the computer to expand the computer's capability. The eight slot connectors provide for user expansion to add features, such as sound capability, fax and modem communication capability, by add-in cards that have these features on them. The expansion add-in adapter cards are inserted into one or more of the eight slots which include eight connectors (sockets) that are mounted and soldered directly on the motherboard. The motherboard has printed circuit wiring that distributes the I/O signals from the add-in cards to appropriate components on the motherboard via an expansion bus. The expansion bus is an extension of the computer's address and data bus.
The prior art has the advantage that the add-in cards are easy to install by even novice users. But, the prior art requires multiple connectors to accommodate the multiple add-in cards which wastes space on the motherboard and results in increased manufacturing costs since it takes time to install and solder each connector. The slots also takes space on the chassis that could be used for I/O.
It is therefore desirable to have an expansion slot design on the motherboard that saves board space, chassis space, and cost.